Federal law (USA) restricts these devices to sale distribution and use by or on the order of physician.

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2 INTRODUCTION This surgical technique describes how to perform an Anatomic Ribbon Surgery ACL reconstruction using an Extracortical Femoral Button and a Tibial Pull Suture Plate. CAUTION Federal law (USA) restricts these devices to sale distribution and use by or on the order of physician. INDICATIONS OF USE Extracortical femoral button: reconstructive therapy of ruptures to the anterior and posterior cruciate ligament by means of autologous grafts. Pull Suture Plate: reconstructive treatment of ruptured anterior and posterior cruciate ligaments by means of autologous grafts. CONTRAINDICATIONS Medacta Anatomic Ribbon Surgery ACL reconstruction using an Extracortical Femoral Button and a Tibial Pull Suture Plate is contraindicated where there is: Osteoporosis and osteomalacia Degenerative osteopathies Adiposity or patient overweight, leading to excessive strain on the fixation button Osteomata in the area in which the fixation button is to be placed Deformities of the bone, or general conditions of the bones which exclude implantation of a fixation button in the opinion of a physician Systemic diseases and metabolic disorders that may compromise the output of the surgery 2

3 INDEX 1. Implants and instruments Overview Implants overview Extra-cortical Femoral Button Tibial Pull Suture Plate (PSP) Instruments Overview Preparation Table Femoral Aimer Femoral Dilator Slide Hammer Tibial Aimer Special k-wire Tibial Dilator Pull Suture Plate Impactor Graft Preparation Setting the graft length Extraction and preparation of the semitendinosus General Information about the graft preparation Three Fold Preparation Four Fold Preparation Graft Reinforcement Tibial side Femoral Side Femoral Button Loop Length Graft thickness measurement Femoral Tunnel Creation K- wires positioning Femoral dilation Tibial Tunnel Creation K- wires positioning and drilling Tibial Dilation Graft Insertion Tibial fixation with the Pull Sutur Plate (PSP) Implants and Instruments Nomenclature This document describes the M-ARS ACL (Medacta Anatomic Ribbon Surgery) surgical technique using harvested autologous semitendinosus ligament. 3

4 1. Implants and instruments Overview 1.1. Implants overview Extra-cortical Femoral Button The extra-cortical femoral button is used for the femoral fixation of the graft. It has to be loaded, through the two central holes, with two USP 2 sutures with a needle at one edge. Two additional sutures USP 2 (better if in a different colour) have to be loaded on the side holes that allows to pull the implant towards the femoral tunnel and to flip it once it has reached an extra-cortical position (inside-out technique). The implant assembled with the sutures is represented in the following picture. The sutures necessary to create the loop, represented hereafter, has to be fixed on the graft by using the preparation table as described in the paragraph 2.4. Sutures for pulling and flipping are assembled only after the graft reinforcement Tibial Pull Suture Plate (PSP) The Tibial Pull Suture Plate (PSP) is an extra cortical fixation device which is fixed in correspondence of the tibial tunnel using a specifically designed impactor The implant has to be assembled with two USP 2 sutures following the path herewith represented. Suture 1 has to be passed along the central holes creating an adjustable loop between the graft and the implant. This suture has to be assembled during the folding and then used for the reinforcement of the graft, the remaining sutures are assembled during the reinforcement phase on the preparation table. Use sutures of two different colours for each side of the graft as represented 4

5 1.2. Instruments Overview Preparation Table The preparation table has been designed to clean and to properly prepare the tendon graft or the ligament implant. It is composed by a main board, a plastic cleaning panel and femoral and tibial clamps. The clamp s shape allows the graft fixation (clamp nose) and the femoral button and tibial Pull Suture Plate lodging. These clamps can slide along a scaled track in order to properly tension the graft. The scale permits the measurement of the length of the tendon graft or the ligament implant. The preparation table enables to: Prepare the tendon graft and set its length; Set the button-loop length; Strengthen the femoral and tibial tips of the tendon graft by applying sutures (reinforcement preparation); Femoral clamp The femoral clamp holds the femoral button and the femoral tip of the tendon graft during the preparation. The length of the button-loop can be set by moving the clamp body, then it can be read by using the scale engraved on the main board. Move down the lower locking bar to fix the clamp. To prevent the tendon graft slippage during the reinforcement preparation, fix the femoral tip in the femoral clamp nose which can be locked using the upper bar Tibial Clamp The tibial clamp holds the Tibial Pull Suture Plate (PSP) and the tibial tip of the tendon graft during the tendon graft preparation. By moving the clamp along the board track, is it possible to tension the tendon graft. Move down the lower bar to fix the clamp. To prevent the tendon graft slippage during the reinforcement preparation, fix the tibial tip in the tibial clamp nose which can be locked using the upper bar. 5

6 Femoral Aimer It is used to create three overlapping holes in the femoral bone in correspondence with the ACL femoral insertion. It consists of a central guiding hole for a Ø2.4 mm k-wire and 2 adjacent guiding holes for Ø2.4 mm k-wires. Furthermore, it features a window at its tip to allow direct vision of the insertion site of the ACL. Femoral Aimers with two different tips configuration are available: 35 and 50 inclination. According to patient anatomy please select the Femoral Aimer that enables to better aim the ACL femoral insertion. The tip is blunt in order to facilitate the positioning on the ACL femoral insertion. The central k-wire (2.4 mm diameter) should be drilled in the middle of the ACL femoral insertion site Femoral Dilator The femoral dilator is cannulated in order to be sled along the central Ø2.4 mm k-wire into the bores created with the femoral aimer. Three sizes are available, according with the graft size. The tip is flat to create the requested femoral tunnel. In order to measure the femoral tunnel depth the femoral dilator is graduated Slide Hammer It has been designed with a self-locking mechanism to be coupled with the femoral or the tibial dilators. It enables easy dilators removal in case of strong friction between the dilators tip and bone. 6

7 Tibial Aimer The tibial Aimer is used to create three overlapping holes in a C-shaped manner. It consists of two different components: Aiming arc (right and left) Bullet: two sizes with dedicated k wire and drills guide The arc has a pin on the tip that allows to correctly position the aimer on the ACL tibial insertion location. A locking lever consent to fix the bullet avoiding any possible slippage. A special k-wire with a diametric reduction, to avoid slippage from the bullet, has to be used. The special k-wire is inserted from the tip of the bullet till the diameter reduction: the tip of the k-wire remains about 2mm out of the tip of the drill sleeve Special k-wire The special K-wire presents a diametric reduction in its posterior portion in order to be easily introduced into the tibial aimer bullet form the front but to prevent its slippage form the bullet (posteriorly) Tibial Dilator The tibial C-shape holes are dilated using the tibial dilator. The size of the tibial dilator is related to the dimension of the graft: three sizes are available. The first two sizes have the same diameter of the tibial drill patterns. An additional dilator size is provided in case the graft is larger. In order to avoid tilting of the dilator, the head is introduced in the tibial bores with the help of 2 lateral guiding k-wires (Ø 2 mm). The k wires freely run along the dilator avoiding any possible condylar damage. In order to avoid incorrect positioning of the dilator, the lateral k-wire are moved upwards until they are visible in the joint. The dilator is then inserted by tapping on its back Pull Suture Plate Impactor The PSP impactor has a specific tip design that mimic the inner contour of the PSP implant: it is used to impact the PSP after the PSP has been approached to the tibial tunnel by pulling the loop suture. Use this instrument to ensure the appropriate extra-cortical fixation of the PSP in correspondence of the tibial tunnel. 7

8 2. Graft Preparation 2.1. Setting the graft length The graft path inside the bone consists of 3 different parts: Femoral tunnel (minimum length 30 mm) Intra-articular path (it depends on joint dimension, usually mm) Tibial tunnel (at least 35 mm) Depending on the length of the graft, the following preparation methods are available: Source Preparation Minimum Length [cm] Semitendinosus 3 Fold Preparation 18 Semitendinosus 4 Fold Preparation 24 Recommended 2.2. Extraction and preparation of the semitendinosus The semitendinosus is harvested using a tendon stripper (as per surgeon preferred technique). The graft is harvested (as in the selected technique) and then cleaned on the plastic panel of the preparation table. The graft can be fixed using the plastic panel clamp. The tendon is cut with a scalpel up to its core through its longitudinal direction (following the tendon fibres direction). Spread the tendon by using the back of a scalpel. A ribbon shaped structure is obtained (1-2 mm thickness, mm width). In addition, the tendon can be spread using the legs of a pair of tweezers. 8

9 2.3. General Information about the graft preparation The graft preparation is carried out in four different steps: the tendon is folded according to the following instruction (see paragraph and 2.3.2) on the plastic preparation board. Only the adjustable loop of tibial implant has to be assembled with the graft; the tendon is positioned between the two clamp s noses; the tendon is reinforced on both sides; sutures for pull and flip the femoral button are assembled with the femoral implant Three Fold Preparation In the 3 Fold preparation the tendon is looped between tibial sutures. The tibial free tip is folded towards the femoral direction within the suture loop of the tibial implant and then the femoral tip is bent towards the tibial side. The graft is tensioned and fixed on the preparation table clamps noses. Reinforce each side using the preparation table as described in the 2.4 paragraph. Perform the reinforcement preparation starting from the tibial side. Check and adjust the tension of the graft before starting the femoral reinforcement preparation Four Fold Preparation Place the tendon in the tibial loop (in the middle of its length, line 2 in the following representation) and then fold it on the tibial side. Fold the graft on the femur side (in the middle of its length, line 1-3 in the following representation). Fix the tendon on the preparation table clamps noses. Reinforce each side using the preparation table as described in the 2.4 paragraph. Perform the reinforcement preparation starting from the tibial side. Check and adjust the tension of the graft before starting the femoral reinforcement preparation. 9

10 2.4. Graft Reinforcement Tibial side Fix the graft and PSP implant construct on the preparation table board clamp as represented. The suture is passed through the adjustable loop and then returned to the graft. Move towards the tibial end. Perform 4-5 reinforcement stitches for each reinforcement as represented below. CAUTION: The adjustable suture loop of the tibial button that goes towards the graft must not be punctured during the reinforcement procedure. The strengthening has to be performed as central as possible and under tension in order to achieve a good fixation of the suture with the tendon graft. Start from the more proximal edge. Pierce only the graft. 10

11 With reference to the description in paragraph 1.1.2, start with the suture 1 (end of the adjustable loop). Then reinforce with an additional suture (2) on the same side and move it towards the lateral hole of the implant (same side). Move on the other side and reinforce in the same way using two sutures of different colour from the latter (3 and 4). Again, pay attention that the loop wire is not punctured. This two sutures are then guided towards the Tibial pull suture plate respectively along the central and lateral hole Femoral Side Reinforce the femoral side as for the tibial side using four sutures (2 for each side, better if of different colour) as represented in paragraph After the reinforcement, open the clamp nozzle on the femoral side, remove the clamp from the rail, turn the clamp of 180 degrees and reinsert it as represented below. Insert the Femoral implant within the dedicated support and move two of the sutures thought the dedicated central holes creating the loop as represented in paragraph NOTE: Examine if all the graft strands are properly tightened. Applied tension by pulling the femoral strands before fixing the femoral length. In alternative move the clamp toward tension the loop. Fix the femoral loop length in accordance to the next paragraph, perform at least five knots for each couple of sutures in order to fix the femoral loop. 11

12 Femoral Button Loop Length In order to properly set the button loop length, consider the femoral channel length (without blind bore/dilation) and the flip path of the button (7 mm). For example: Channel length = 40 mm Blind Hole/Dilation Length = 30 mm (minimum) Flip path = 7 mm In this case the button loop length has to be 17 mm ( ). Please consider that if the button loop length is too long, it leads to a reduced contact between the graft and the bone and this can affect the stability of the reconstructed ACL Graft thickness measurement The graft measuring device has three slots to measure the size of the graft. The slots have an opening through which sutures can be passed. All the edges are rounded to avoid harming of tendon during measurement. The instrument is inserted from the femoral side of the graft, while the graft is assembled on the preparation table. After its insertion, the measurement device is rotated by 90 degrees around the suture filaments. The device is then moved through the reinforcement filaments. Moving the device, a slight resistance should be felt. 12

13 Read the thickness of the graft. This measure is important to set the dimension of the bone tunnels. In order to maintain the graft moist, use a moistened sterile cloth 3. Femoral Tunnel Creation The femoral tunnel creation consists of two main steps, as described below K- wires positioning Bend the knee at 120 degrees of flexion. Position the femoral aimer on the ACL femoral insertion site. Insert the central k-wire in the central hole of the aimer and drill it through the femur. The k-wire has to come out in the extra cortical femoral button desired position. Orientate the guide accordingly. 13

14 Insert further the central k-wire in order to align the proximal laser marking with the femoral condyle intraarticular cortical surface. Remove the Femoral aimer and check if the k-wire is properly placed. Re-Insert the femoral aimer by coupling the tip with the proximal portion of the central k-wire. Insert the two lateral k-wires for approximately 30 mm. Remove the Femoral Aimer and over drill the lateral k- wires up to 30 mm depth. Check the depth of the hole while drilling. During the transition between trabecular to contro-cortical bone there is a significant increase of drilling resistance. An over drilling in the cortical bone must be avoided. Remove the two lateral k-wires and keep the central k- wire in place. Slide the reverse length gauge from the distal portion of the central k-wire that protrudes from the femur. Using the distal marking on the k-wire check the femoral tunnel length on the length gauge. 14

15 3.2. Femoral dilation Dilate according to the graft size. Insert the dilator (along the central k wire) in the drilled bone canal by tapping the back of the dilator. Proceed slowly to avoid potential posterior blow out. Read the markings to create a socket of 30 mm. After the dilation, check the depth of the canal and the absence of bony fragments in the canal. It is also necessary to ensure that the cortex has not been damaged and is suitable for the fixation of the button CAUTION: It is important that the dilation is carried out step by step: for example, for a Medium size graft, start to dilate with size Small and then use the Medium size. Remove the dilator and drill the bone along the central k-wire with a cannulated drill until the extra-articular cortical bone is reached. The socket (30 mm minimum depth) with the central femoral tunnel (4.5 mm diameter) has now been created. Remove the central k-wire. 4. Tibial Tunnel Creation The tibial tunnel creation consist of two main steps, as described below K- wires positioning and drilling Insert the special k-wire within the bullet, see red arrow. It protrudes from the bullet tip (about 2 mm). The k-wire is not fixed inside the bullet, in order to allow instant drilling after the aimer positioning. NOTE: Handling the bullet, keep in mind that the special k- wire cannot slip posteriorly but it can slip anteriorly. Insert the bullet into the tibial arc from behind (see red arrow). The arc is designed so that there can be no wrong orientation of the bullet if the correct arc configuration (left/right) is used. 15

16 The tip is inserted into the medial portal and is positioned targeting the ACL tibial insertion location (use the anterior horn of the lateral meniscus insertion as a reference). The bullet is advanced towards the tibia. The length of the tibia drilled canal can be read using the scale marked on the bullet. The length should be at least 35 mm. Drill the special k-wire, till the tip is visible in the joint. In case that the k-wire is not in the center, check if the tibial aimer has been displaced and thereby the k-wire has been bent. Repeat the previous steps until the k-wire is placed in the center of the pattern. The first hole is performed using the shortest drill (4.5 mm in diameter) till its tip is visible in the joint. Pay attention to not damage femoral cartilage. The drill avoids the rotation of the tibial arc around the central k-wire. Perform the second hole using the longest drill (4.5 mm in diameter) till its tip is visible in the joint. A C-shaped pattern is obtained. The drills can be removed. Remove the bullet, the aimer and the central k-wire. 16

17 4.2. Tibial Dilation Insert the two guidewires in the tibial dilator. Insert the dilator. In order to prevent incorrect orientation of the dilator into the tibial canal/tunnel, the guide wires are advanced until they are visible in the joint. These k-wires show the orientation of the dilator during the entire dilation procedure. The tibial dilator, by tapping the back of the handle, is inserted in the tibia tunnel until the first edge comes out from the tibial plateau. The C-shaped holes on the tibial plateau and on the entry point of the tibial tunnel are represented. The hole on the tibial plateau should correspond to the tibial insertion site of the ACL. CAUTION: It is important that the dilation is carried out step by steps: for example, for a Medium size graft, start to dilate with Small size and then use the Medium size. NOTE: as the tibial drill patterns prepare the tunnel for sizes Small and Medium, in case of ligament graft of size Large please follow the following instructions (especially in case of hard/sclerotic bone) GRAFT SIZE SMALL MEDIUM LARGE Bullet Size Small Medium Medium Dilator Size Small Small+Medium Small+Medium+Large 17

18 5. Graft Insertion The Femoral button is represented with the pre-set button suture length and specifically: (1) Femoral button hole for the pulling suture (2) Femoral button hole for the tilting suture (minimal suture size: USP2/EP5). The Tibial PSP is represented with the suture loop described in paragraph 1.1. Please check if the suture loop can be shortened by pulling on the suture loop. To better control the twisting of the graft in the joint during the insertion, it can be helpful to mark the posteromedial edge of the ligament with a marker. Both the pulling and the tilting sutures of the femoral button are inserted trans-tibially using a passing k-wire. In order to assure that the PSP can properly accommodate within the graft tunnel without twisting of the suture, the correct alignment into the prepared bore has to be checked. The femoral end of the graft is visible in the joint. In the picture, the posteromedial edge of the ligament is marked by a black line (for illustrative purpose). 18

19 In order to mimic the rotation of the cruciate ligament, the posterior graft sutures (b) are pulled in the anterior direction from behind the anterior pair of sutures (a) by using a probe in order to twist the graft. The graft is twisted and at the same time towed in the femoral tunnel by pulling on the pulling suture. The anterior tibial portion of the graft (a) gets in contact posteriorly with the femur (b) which reflects the twisting of the anteromedial and the posterolateral portions of the ACL in flexion. Once the femoral button is towed outside the femoral tunnel, pull on the tilting suture to flip the femoral button. By pulling backwards the graft please check that the femoral button is in contact with the cortical bone and holds the graft firmly. The graft should remain at least 20 mm inside the femoral tunnel. In case that the button loop length results too short and therefore the femoral button cannot be properly flipped, pull the graft out of the femoral tunnel and further dilate the femoral tunnel using the femoral dilator to create enough room for the button to flip. Articulate the knee to improve the graft seat and tension. In extension the graft is positioned and clamped to the front. The tensioning and the fixation of the graft is then carried out in a 30 of flexion. 6. Tibial fixation with the Pull Sutur Plate (PSP) Pull the PSP towards the tibia by pulling the loop suture (a). Pull until the PSP body is sunk into the tibial tunnel and its edges seat on the tibial cortex. Use the PSP impactor to ensure the appropriate extra-cortical fixation of the PSP in correspondence of the tibial tunnel. Further pulling increase the tension of the graft. Pay attention to the bending angle of the knee. The tensioning/knotting phase should be performed in a 30 of flexion. Compare the mobility and stability of the knee with the contralateral one. Cycle the leg at least 20 times before the final fixation of the pull suture plate. Knot the sutures from the inner holes with 5 knots. Note that the pulling suture is held under tension. If desired, the knot can be pushed with a knot holder (not provided). Take the end of the two knotted suture and knot each of it with the suture of the closest side hole. Make 5 knots to achieve a stable fixation. The protruding threads are cut 2-3 mm above the knots. 19

20 7. Implants and Instruments Nomenclature Ref. No. Description Picture Tibial Pull Suture Plate (PSP) Extracortical Femoral Button Ref. No. Description Picture 05.05S.001 Sports medicine - Knee general tray (1 level) 05.05S.002 Sports medicine - M-ARS ACL tray (2 levels) 05.05S.004 Sports medicine - Knee prep. table tray (1 level) NOTE FOR STERILISATION The instrumentation is not sterile upon delivery. It must be cleaned before use and sterilised in an autoclave respecting the US regulations, directives where applicable and following the instructions for use of the autoclave manufacturer. For detailed instructions please refer to the document Recommendations for cleaning decontamination and sterilization of Medacta International orthopaedic devices available at 20

21 NOTES 21

22 M-ARS ACL System Surgical Technique Ref: US Rev.00 CE Last update: March 2017